1. Field of Invention
The present invention relates to electric toy guns and more particularly, to ballistic adjustment device for use in a toy gun for adjustment of the ballistic range, which enhances bullet positioning stability and the stability of bullet ballistic trajectory.
2. Description of Related Arts
During operation of a conventional electric toy gun, a bullet (air-soft bullet) is fed into the rear end of the gun barrel and then driven out of the gun barrel. Due to the consideration of cost, the gun barrel of a toy gun does not provide a spiral line (rifling) on the inside wall thereof to guide the fired bullet along a spiral way. In consequence, the control of the bullet ballistic trajectory in a toy guy is difficult.
In view of the aforesaid problem, Taiwan Utility Patent Publication No. 299663 and Taiwan Utility Patent No. M298109 disclose the use of a ballistic adjustment device in a toy gun. However, these designs do not fit all different toy guns. For example, a big scale toy gun cannot use the aforesaid ballistic adjustment device directly. For use in a big scale toy gun, the aforesaid ballistic adjustment device must be modified.
FIG. 1 illustrates a ballistic adjustment device A0 for use in a big scale toy gun according to the prior art. According to this design, the ballistic adjustment device A0 is installed in the rear end of the toy gun's gun barrel 10, which has an end notch 101 (see FIG. 2). The ballistic adjustment device A0 comprises a bullet barrel 20, a pressure member 30 and a rotary control member 40 (see FIG. 2). Further, the ballistic adjustment device A0 is coupled to the gun barrel liner A02 by a coupling device A01 (see FIG. 1). The bullet barrel 20 is an elastic member (made of rubber or plastics) attached to the rear end of the gun barrel 10 (see FIG. 3), comprising a press portion 201 and an inside protruding block 202 (see FIG. 4) corresponding to the end notch 101 of the gun barrel 10, a rounded recess 203 located on the press portion 201, and an inside annular flange 204 (see FIG. 3). The inside protruding block 202 has a smoothly arched bottom recess. The pressure member 30 is a round ball accommodated in the rounded recess 203 of the bullet barrel 20. The rotary control member 40 is rotatably coupled to the rear end of the gun barrel 10 around the bullet barrel 20 and the pressure member 30, having an eccentric groove 401 located on the inside wall thereof (that has its one end made relatively deeper than its other end). The pressure member 30 is partially accommodated in the rounded recess 203 of the bullet barrel 20 and partially accommodated in the eccentric groove 401 of the rotary control member 40.
When rotating the rotary control member 40 relative to the gun barrel 10, the eccentric groove 401 is moved relative to the pressure member 30 to adjust the pressure at the pressure member 30, i.e. the elevation of the pressure member 30 is adjusted subject to rotation of the rotary control member 40 (see FIGS. 4 and 5). When the pressure member 30 is lowered, the inside protruding block 202 is relatively lowered. Before firing, a bullet 50 is fed into the bullet barrel 20 and stopped in position by the inside annular flange 204. When fired (see FIG. 6), the bullet 40 is forced over the inside annular flange 204, and rotated forwards subject to friction from the inside protruding block 202. Thus, adjusting the elevation of the inside protruding block 202 relatively adjust the ballistic trajectory.
However, this design of ballistic adjustment device still has drawbacks as follows:
1. The bullet 50 is a rounded member. When the inside protruding block 202 is lowered, the smoothly arched bottom recess of the inside protruding block 202 is elastically deformed into a substantially planar condition (see FIG. 5), reducing its contact area with the bullet 50. At this time, a gap exists between the bullet 50 and the bullet barrel 20. Thus, the bullet 50 may be not accurately kept in axial alignment with the axis of the gun barrel 10 affecting the stability of the ballistic trajectory.
2. If the bullet 50 is a defective member (not a perfect sphere, or having recessed and/or raised surface portions), friction between the inside protruding block 202 and the bullet 50 may cause a lateral pressure, affecting the moving angle of the ballistic trajectory.
3. The bullet barrel 20 is simply attached to the rear end of the gun barrel 10. When rotating the rotary control member 40, the bullet barrel 20 may be accidentally rotated relative to the gun barrel 10 by the rotary control member 40, lowering the accuracy of friction between the bullet 50 and the bullet barrel 20 and causing ballistic trajectory instability and a low hit-rate.